String.IndexOfAny Method

Definition

Reports the index of the first occurrence in this instance of any character in a specified array of Unicode characters. The method returns -1 if the characters in the array are not found in this instance.

Reports the zero-based index of the first occurrence in this instance of any character in a specified array of Unicode characters. The search starts at a specified character position and examines a specified number of character positions.

IndexOfAny(Char[])

Reports the zero-based index of the first occurrence in this instance of any character in a specified array of Unicode characters.

Exceptions

Examples

using System;
public class Example
{
public static void Main()
{
char[] chars = { 'a', 'e', 'i', 'o', 'u', 'y',
'A', 'E', 'I', 'O', 'U', 'Y' };
String s = "The long and winding road...";
Console.WriteLine("The first vowel in \n {0}\nis found at position {1}",
s, s.IndexOfAny(chars) + 1);
}
}
// The example displays the following output:
// The first vowel in
// The long and winding road...
// is found at position 3

Module Example
Public Sub Main()
Dim chars() As Char = { "a"c, "e"c, "i"c, "o"c, "u"c, "y"c,
"A"c, "E"c, "I"c, "O"c, "U"c, "Y"c }
Dim s As String = "The long and winding road..."
Console.WriteLine("The first vowel in {2} {0}{2}is found at position {1}",
s, s.IndexOfAny(chars) + 1, vbCrLf)
End Sub
End Module
' The example displays the following output:
' The first vowel in
' The long and winding road...
' is found at position 3

Remarks

Index numbering starts from zero.

The search for anyOf is case-sensitive. If anyOf is an empty array, the method finds a match at the beginning of the string (that is, at index zero).

This method performs an ordinal (culture-insensitive) search, where a character is considered equivalent to another character only if their Unicode scalar values are the same. To perform a culture-sensitive search, use the CompareInfo.IndexOf method, where a Unicode scalar value representing a precomposed character, such as the ligature "Æ" (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture.

Exceptions

Examples

The following example finds the index of the occurrence of any character of the string "is" within a substring of another string.

// Sample for String::IndexOfAny(Char[], Int32)
using namespace System;
int main()
{
String^ br1 = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
String^ br2 = "0123456789012345678901234567890123456789012345678901234567890123456";
String^ str = "Now is the time for all good men to come to the aid of their party.";
int start;
int at;
String^ target = "is";
array<Char>^anyOf = target->ToCharArray();
start = str->Length / 2;
Console::WriteLine();
Console::WriteLine( "The first character occurrence from position {0} to {1}.", start, str->Length - 1 );
Console::WriteLine( "{1}{0}{2}{0}{3}{0}", Environment::NewLine, br1, br2, str );
Console::Write( "A character in '{0}' occurs at position: ", target );
at = str->IndexOfAny( anyOf, start );
if ( at > -1 )
Console::Write( at );
else
Console::Write( "(not found)" );
Console::WriteLine();
}
/*
The first character occurrence from position 33 to 66.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.
A character in 'is' occurs at position: 49
*/

// Sample for String.IndexOfAny(Char[], Int32)
using System;
class Sample {
public static void Main()
{
string br1 = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
string br2 = "0123456789012345678901234567890123456789012345678901234567890123456";
string str = "Now is the time for all good men to come to the aid of their party.";
int start;
int at;
string target = "is";
char[] anyOf = target.ToCharArray();
start = str.Length/2;
Console.WriteLine();
Console.WriteLine("The first character occurrence from position {0} to {1}.",
start, str.Length-1);
Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str);
Console.Write("A character in '{0}' occurs at position: ", target);
at = str.IndexOfAny(anyOf, start);
if (at > -1)
Console.Write(at);
else
Console.Write("(not found)");
Console.WriteLine();
}
}
/*
The first character occurrence from position 33 to 66.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.
A character in 'is' occurs at position: 49
*/

' Sample for String.IndexOfAny(Char[], Int32)
Class Sample
Public Shared Sub Main()
Dim br1 As String = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-"
Dim br2 As String = "0123456789012345678901234567890123456789012345678901234567890123456"
Dim str As String = "Now is the time for all good men to come to the aid of their party."
Dim start As Integer
Dim at As Integer
Dim target As String = "is"
Dim anyOf As Char() = target.ToCharArray()
start = str.Length / 2
Console.WriteLine()
Console.WriteLine("Search for a character occurrence from position {0} to {1}.", _
start, str.Length - 1)
Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str)
Console.Write("A character in '{0}' occurs at position: ", target)
at = str.IndexOfAny(anyOf, start)
If at > - 1 Then
Console.Write(at)
Else
Console.Write("(not found)")
End If
Console.WriteLine()
End Sub
End Class
'
'
'Search for a character occurrence from position 33 to 66.
'0----+----1----+----2----+----3----+----4----+----5----+----6----+-
'0123456789012345678901234567890123456789012345678901234567890123456
'Now is the time for all good men to come to the aid of their party.
'
'A character in 'is' occurs at position: 49
'

Remarks

Index numbering starts from zero. The startIndex parameter can range from 0 to one less than the length of the string instance.

The search ranges from startIndex to the end of the string.

The search for anyOf is case-sensitive.

This method performs an ordinal (culture-insensitive) search, where a character is considered equivalent to another character only if their Unicode scalar value are the same. To perform a culture-sensitive search, use the CompareInfo.IndexOf method, where a Unicode scalar value representing a precomposed character, such as the ligature "Æ" (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture.

See also

IndexOfAny(Char[], Int32, Int32)

Reports the zero-based index of the first occurrence in this instance of any character in a specified array of Unicode characters. The search starts at a specified character position and examines a specified number of character positions.

Exceptions

count + startIndex is greater than the number of characters in this instance.

Examples

The following example finds the index of the occurrence of any character of the string "aid" within a substring of another string.

// Sample for String::IndexOfAny(Char[], Int32, Int32)
using namespace System;
int main()
{
String^ br1 = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
String^ br2 = "0123456789012345678901234567890123456789012345678901234567890123456";
String^ str = "Now is the time for all good men to come to the aid of their party.";
int start;
int at;
int count;
String^ target = "aid";
array<Char>^anyOf = target->ToCharArray();
start = (str->Length - 1) / 3;
count = (str->Length - 1) / 4;
Console::WriteLine();
Console::WriteLine( "The first character occurrence from position {0} for {1} characters.", start, count );
Console::WriteLine( "{1}{0}{2}{0}{3}{0}", Environment::NewLine, br1, br2, str );
Console::Write( "A character in '{0}' occurs at position: ", target );
at = str->IndexOfAny( anyOf, start, count );
if ( at > -1 )
Console::Write( at );
else
Console::Write( "(not found)" );
Console::WriteLine();
}
/*
The first character occurrence from position 22 for 16 characters.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.
A character in 'aid' occurs at position: 27
*/

// Sample for String.IndexOfAny(Char[], Int32, Int32)
using System;
class Sample {
public static void Main()
{
string br1 = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
string br2 = "0123456789012345678901234567890123456789012345678901234567890123456";
string str = "Now is the time for all good men to come to the aid of their party.";
int start;
int at;
int count;
string target = "aid";
char[] anyOf = target.ToCharArray();
start = (str.Length-1)/3;
count = (str.Length-1)/4;
Console.WriteLine();
Console.WriteLine("The first character occurrence from position {0} for {1} characters.", start, count);
Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str);
Console.Write("A character in '{0}' occurs at position: ", target);
at = str.IndexOfAny(anyOf, start, count);
if (at > -1)
Console.Write(at);
else
Console.Write("(not found)");
Console.WriteLine();
}
}
/*
The first character occurrence from position 22 for 16 characters.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.
A character in 'aid' occurs at position: 27
*/

' Sample for String.IndexOfAny(Char[], Int32, Int32)
Class Sample
Public Shared Sub Main()
Dim br1 As String = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-"
Dim br2 As String = "0123456789012345678901234567890123456789012345678901234567890123456"
Dim str As String = "Now is the time for all good men to come to the aid of their party."
Dim start As Integer
Dim at As Integer
Dim count As Integer
Dim target As String = "aid"
Dim anyOf As Char() = target.ToCharArray()
start =(str.Length - 1) / 3
count =(str.Length - 1) / 4
Console.WriteLine()
Console.WriteLine("The first character occurrence from position {0} for {1} characters.", start, count)
Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str)
Console.Write("A character in '{0}' occurs at position: ", target)
at = str.IndexOfAny(anyOf, start, count)
If at > - 1 Then
Console.Write(at)
Else
Console.Write("(not found)")
End If
Console.WriteLine()
End Sub
End Class
'
'The first character occurrence from position 22 for 16 characters.
'0----+----1----+----2----+----3----+----4----+----5----+----6----+-
'0123456789012345678901234567890123456789012345678901234567890123456
'Now is the time for all good men to come to the aid of their party.
'
'A character in 'aid' occurs at position: 27
'

Remarks

The search begins at startIndex and continues to startIndex + count -1. The character at startIndex + count is not included in the search.

Index numbering starts from zero. The startIndex parameter can range from 0 to one less than the length of the string instance.

The search for anyOf is case-sensitive.

This method performs an ordinal (culture-insensitive) search, where a character is considered equivalent to another character only if their Unicode scalar value are the same. To perform a culture-sensitive search, use the CompareInfo.IndexOf method, where a Unicode scalar value representing a precomposed character, such as the ligature "Æ" (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture.